Quote Originally Posted by rossbotics View Post
Hi Taper
That's what I did I used two 1/2" X 1" X 8" hardened parallels on there edge and spaced them up on parallels from the bottom of the mill vise, and spaced up the swing arm as well, this way equal pressure was applied throughout the swing arm for milling the slot, worked great.

O-1 tool steel is not difficult to heat treat at all, beings you have a furnace just heat it up to around 1500 deg, and quench her in oil then clean it up nice and shinny and reheat it until it turns to a straw color and quench it once more, it's now tempered, here's a link to all the specs, http://buffaloprecision.com/data_sheets/DSO1TSbpp.pdf
I've made lathe form tools from O-1 drill rod. As well shafts for needle bearings to run on, and sand blast nozzles (which I don't temper). I did have one mishap, I made a replacement bandsaw blade tension bolt for my 4x6 import saw. The original bolt stripped out. I thought, "I don't need to temper this", well it didn't take to long for the shaft just above the threads to fail. Snapped right off. It did teach me that tempering was a required process if you don't want it to shatter like glass.

So what is your method of cleaning up the burnt oil residue? I've found removal to be a PITA to get a clean surface.